1. Field of the Invention
This invention relates to an additive for use in metal refining and a process for preparing the same. The additive comprises metallic magnesium and calcium carbide, and is useful particularly as a desulfurizer for a molten pig iron, as an inoculant for spheroidal graphite cast-iron and as a dephosphorizer for various molten metals.
2. Description of the Prior Art
Both calcium carbide and metallic magnesium have heretofore been widely used as a metal-refining aadditive, such as a desulfurizer and a dephosphorizer. Calcium carbide possesses some defects, which are such that, when it is used in the desulfurization of a molten pig iron or the preparation of spheroidal graphite cast-iron, calcium carbide exhibits a low conversion and inevitably produces a slag containing a salient amount of calcium carbide. Metallic magnesium also possesses some defects, which are such that, metallic magnesium causes a radical reaction because of its relatively high vapor pressure and, hence, the operation is dangerous and the reaction efficiency is low.